Do weather conditions drastically change from morning to night or one area to the next?
Lake Roosevelt is semi-arid climate lies to the west of the Cascades and east of the Rockies. In comparison to Western Washington it is much drier, with summers that are hotter and winters that are colder. Average January temperatures in eastern Washington range from less than -7°C (20°F) to -1°C (30°F), often dropping down to -18°C (0°F). July averages are from 18° to 24°C (65° to 75°F). However, daytime temperatures are often above 32°C (90°F). The climate within the Lake Roosevelt watershed varies a great deal from one end of the lake to the other. The southern portion of the lake near Grand Coulee is hotter and dryer. Average annual precipitation near the dam is about 10 inches. Area vegetation includes shrub steppe species like sagebrush and bitterbrush. The areas around the northern end of Lake Roosevelt receive considerably more precipitation. The region around Colville for instance receives about 17 inches a year, enough to support ponderosa pine and Douglas-fir. As the lake ge
